Modulation of cell adhesion to conductive polymers

Our work on conductive polymer (CP) systems grafted with stimuli-responsive polymer brushes is motivated by the prospect of precisely controlling cellular behaviour by tailored smart interfaces. Here, the effects on cell adhesion by applying a potential to poly(3,4-ethylenedioxythiophene) (PEDOT) during both protein coating and cell culture is investigated. The results highlight the importance of pre-adsorbing fibronectin in this case, especially for the reduced polymer which binds protein strongly. The effects of changing the surface chemistry of the PEDOT electrode by grafting of brushes by atom transfer radical polymerisation (ATRP) is also investigated. Specifically, the composition of the salt-sensitive poly(oligo(ethylene glycol methyl ether methacrylate))-based brushes was tailored to control the level of cell adhesion to the interface. The composition, and also the length of the grafted brushes was seen to be important to the cell adhesion. It is also demonstrated how PEDOT films grafted with a protein and cell rejecting brush can be converted to a cell adhesive state by attaching an integrin ligand to the brush to mediate cell adhesion.